I hope to write more on what I called the unities of Thessalonians using passages from elsewhere to further show that the Resurrection from the dead along with the Rapture was (past tense) a unique one-time event, not something in two stages nor something wholly in the future.
But first it might be good to get the Man of Sin (MoS) out of the way. The MoS is both a necessary and helpful boogeyman for futurist theologians. It is necessary because if they assume that the Second Coming of Christ is still future then the Man of Sin, “the Antichrist” (sic) is too. It is helpful because it is an ever-useful tool for all kinds of merchandising. Plus, using a phrase from my Preacher Boys class, “It preaches!”
But a piece of bad doctrine, like a bad apple in a basket, does not keep its badness to itself. Soon other apples deteriorate.
It is the same with bad eschatology. If you think that the Second Coming, Antichrist, Tribulation – the whole show – are still future you overlook entirely other interpretations. You overlook or downplay the bad guys (1st-century Jews) and replace them others who had nothing to do with these passages (the Papacy or, according to some futurists, Islam).
Case in point is the following passage, 2nd Thess. 2:3-8:
3, ¶ Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that man of sin be revealed, the son of perdition;
4, Who opposeth and exalteth himself above all that is called God, or that is worshipped; so that he as God sitteth in the temple of God, shewing himself that he is God.
5, Remember ye not, that, when I was yet with you, I told you these things?
6, And now ye know what withholdeth2 that he might be revealed in his time.
7, For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way.
8, And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming:”